在 2024/6/26 下午8:10, Philippe Mathieu-Daudé 写道:
Hi Bibo,
On 26/6/24 06:11, maobibo wrote:
On 2024/6/5 上午10:15, Jiaxun Yang wrote:
It was missed out in previous commit.
Fixes: b4a12dfc2132 ("hw/intc/loongarch_ipi: Rename as loongson_ipi")
Signed-off-by: Jiaxun Yang <jiaxun.y...@flygoat.com>
---
hw/intc/loongarch_ipi.c | 347
------------------------------------------------
1 file changed, 347 deletions(-)
-static void loongarch_ipi_realize(DeviceState *dev, Error **errp)
-{
- LoongArchIPI *s = LOONGARCH_IPI(dev);
- SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
- int i;
-
- if (s->num_cpu == 0) {
- error_setg(errp, "num-cpu must be at least 1");
- return;
- }
-
- memory_region_init_io(&s->ipi_iocsr_mem, OBJECT(dev),
&loongarch_ipi_ops,
- s, "loongarch_ipi_iocsr", 0x48);
-
- /* loongarch_ipi_iocsr performs re-entrant IO through ipi_send */
- s->ipi_iocsr_mem.disable_reentrancy_guard = true;
-
- sysbus_init_mmio(sbd, &s->ipi_iocsr_mem);
-
- memory_region_init_io(&s->ipi64_iocsr_mem, OBJECT(dev),
- &loongarch_ipi64_ops,
- s, "loongarch_ipi64_iocsr", 0x118);
- sysbus_init_mmio(sbd, &s->ipi64_iocsr_mem);
It is different with existing implementation.
With hw/intc/loongson_ipi.c, every vcpu has one ipi_mmio_mem, however
on loongarch ipi machine, there is no ipi_mmio_mem memory region.
So if machine has 256 vcpus, there will be 256 ipi_mmio_mem memory
regions. In function sysbus_init_mmio(), memory region can not exceed
QDEV_MAX_MMIO (32). With so many memory regions, it slows down memory
region search speed also.
void sysbus_init_mmio(SysBusDevice *dev, MemoryRegion *memory)
{
int n;
assert(dev->num_mmio < QDEV_MAX_MMIO);
n = dev->num_mmio++;
dev->mmio[n].addr = -1;
dev->mmio[n].memory = memory;
}
Can we revert this patch? We want to do production usable by real
users rather than show pure technology.
Since commit b4a12dfc2132 this file is not built/tested anymore:
-specific_ss.add(when: 'CONFIG_LOONGARCH_IPI', if_true:
files('loongarch_ipi.c'))
+specific_ss.add(when: 'CONFIG_LOONGSON_IPI', if_true:
files('loongson_ipi.c'))
We don't want to maintain dead code.
Hi, Philippe
It is commmit 49eba52a5 that causes Loongarch to fail to start.
What bibao means is that LoongArch and mips do not share "lloongson_ipi.c".
This avoids mutual influence.
My understanding of the next sentence is as follows.
Nowadays, most of the open source operating systems in China use the
latest QEMU.
e.g. OpenEuler/OpenAnolis/OpenCloudOS, etc. These operating systems have
a large
number of real users. so we need to maintain the stability of the
LoongArch architecture
of the QEMU community as much as possible. This will reduce maintenance
costs.
Therefore, we would like to restore the 'loongarch_ipi.c' file. what do
you think?
Thanks.
Song Gao
Regards,
Phil.
